Portfolio efficiency analysis with SFA: the case of PSI-20 companies Nuno Barbosa Ferreira, Manuela M. Oliveira Applied Economics, 2016 This study aimed to assess the technical efficiency (TE) of individual companies and their respective sectors that are traded on the Portuguese stock market. We accomplished this by combining the internal input variables (e.g., ‘market value and return’) with exogenous variables (e.g., ‘interest income’, ‘depreciation’, ‘cost of goods’, ‘employees’ and ‘net sales’) into a Stochastic Frontier Analysis (SFA) model. The TE of the PSI-20 (Portuguese Stock Index) was estimated using factors that affect efficiency variability. The main advantage of using the SFA approach is its potential to discriminate between measurement error and systematic inefficiencies in the estimation process. The results demonstrated that TE is higher for enterprises in the industrial, construction and distribution sectors, whereas the commercial banking sector has the lowest TE scores. The ‘employees’ and ‘depreciation’ are the variables which most contribute to stock market inefficiency.
A system dynamics model to support the management of artisanal dredge fisheries in the south coast of Portugal J.H. Martins, A.S. Camanho, M.M. Oliveira, M.B. Gaspar International Transactions in Operational Research, 2015 This paper presents a management model developed to promote the sustainability of artisanal fisheries, considering socioeconomic and environmental dimensions. The management of artisanal fisheries faces many challenges, including the lack of appropriate tools to support policy makers and stakeholders in the decision‐making process. The model presented in this study is based on system dynamics and allows the simulation of the behavior of the artisanal dredge fishery on the south coast of Portugal, including four main species and two fleets. Two scenarios were simulated to assess the impact of regulatory measures on the system sustainability: scenario 1 simulated a permanent reduction of fishing effort, returning an improvement of biologic and economic sustainability; scenario 2 simulated the closure of one species for a period of one year to allow its recovery. It was found that although the revenue of fisheries decreases in that year, the system is able to return to the average levels of revenue three years after the closure. The study aimed to guide decision makers in the selection of the most appropriate measures toward the preservation of marine ecosystems and socioeconomic stability of fishing communities. The developed system dynamics model, combining available data with knowledge of fisheries experts, proved to be a useful scientific tool to identify management policies and organizational structures leading to greater success. This technique can be applied to the study of other fishery systems worldwide.
Diclidophora luscae (Monogenea: Diclidophoridae) in pouting, Trisopterus luscus (Linnaeus, 1758) from the northeast Atlantic; epidemiology, morphology … P Ramos, R Varandas, IL Conceição, A Grade, MM Oliveira, ... Parasitology Research 121 (9), 2517-2535 , 2022 2022 Citations: 2
Do fisher associations really represent their members’ needs and opinions? The case study of the octopus fishery in the Algarve (south Portugal) M Rangel, C Pita, MM de Oliveira, MH Guimarães, R Rainha, ... Marine Policy 101, 276-284 , 2019 2019 Citations: 22
Forecasting bivalve landings with multiple regression and data mining techniques: The case of the Portuguese Artisanal Dredge Fleet MM Oliveira, AS Camanho, JB Walden, VL Migueis, NB Ferreira, ... Marine Policy 84, 110-118 , 2017 2017 Citations: 10
Evaluating the influence of skipper skills in the performance of Portuguese artisanal dredge vessels MM Oliveira, AS Camanho, JB Walden, MB Gaspar ICES Journal of Marine Science 73 (10), 2721-2728 , 2016 2016 Citations: 17
Portfolio efficiency analysis with SFA: the case of PSI-20 companies NB Ferreira, MM Oliveira Applied Economics 48 (1), 1-6 , 2016 2016 Citations: 12
Predicting revenue efficiency of the Portuguese artisanal dredge fishery using external factors N Ferreira, M Oliveira, J Walden, AM Camanho 2016
Exploring Linkages of the Emergent Economies under a European Sovereign Debt Crisis Context N Ferreira, M Oliveira 2016
A system dynamics model to support the management of artisanal dredge fisheries in the south coast of Portugal JH Martins, AS Camanho, MM Oliveira, MB Gaspar International Transactions in Operational Research 22 (4), 611-634 , 2015 2015 Citations: 19
The phycotoxins׳ impact on the revenue of the Portuguese artisanal dredge fleet MM Oliveira, AS Camanho, MB Gaspar Marine Policy 52, 45-51 , 2015 2015 Citations: 14
A system dynamics model to support the management of artisanal dredge fisheries in the south coast of Portugal JM Hora, A Camanho, MM Oliveira, M Gaspar 2015
Untangling hotel industry’s inefficiency: An SFA approach applied to a renowned Portuguese hotel chain N Ferreira, M Oliveira Untangling hotel industry’s inefficiency: An SFA approach applied to a … , 2015 2015
Assessing technical and economic efficiency of the artisanal dredge fleet in the Portuguese West Coast MM Oliveira, AS Camanho, MB Gaspar Operational Research: IO 2013-XVI Congress of APDIO, Bragança, Portugal … , 2015 2015 Citations: 2
Enhancing the performance of quota managed fisheries using seasonality information: the case of the Portuguese artisanal dredge fleet MM Oliveira, AS Camanho, MB Gaspar Marine Policy 45, 114-120 , 2014 2014 Citations: 13
A novel and simple approach to define artisanal fisheries in Europe L García-Flórez, J Morales, MB Gaspar, D Castilla, E Mugerza, P Berthou, ... Marine Policy 44, 152-159 , 2014 2014 Citations: 68
Application of Bio-Economic Models in the Management of the Dredge Fleet in Portugal MMC de Oliveira PQDT-Global , 2014 2014 Citations: 1
An analysis of equity markets cointegration in the European sovereign debt crisis NB Ferreira, MM Oliveira Open Journal of Finance, 40-48 , 2014 2014 Citations: 5
Modelo de apoio à gestão da pescaria de bivalves com ganchorra no Algarve baseado em dinâmica de sistemas A Camanho, JM Hora, MM Oliveira, MB Gaspar 2014
Nonlinearities in the EU sovereign debt crisis N Ferreira, MM Oliveira 2014
Portfolio technical efficiency assessment with DEA: the case of the PSI-20 enterprises N Ferreira, MM Oliveira 2014
The influence of catch quotas on the productivity of the Portuguese bivalve dredge fleet MM Oliveira, AS Camanho, MB Gaspar ICES Journal of Marine Science 70 (7), 1378-1388 , 2013 2013 Citations: 16
MOST CITED SCHOLAR PUBLICATIONS
A novel and simple approach to define artisanal fisheries in Europe L García-Flórez, J Morales, MB Gaspar, D Castilla, E Mugerza, P Berthou, ... Marine Policy 44, 152-159 , 2014 2014 Citations: 68
Productivity change of the artisanal fishing fleet in Portugal: a Malmquist index analysis MM Oliveira, MB Gaspar, JP Paixão, AS Camanho Fisheries Research 95 (2-3), 189-197 , 2009 2009 Citations: 59
Technical and economic efficiency analysis of the Portuguese artisanal dredge fleet MM Oliveira, AS Camanho, MB Gaspar ICES Journal of Marine Science 67 (8), 1811-1821 , 2010 2010 Citations: 38
Do fisher associations really represent their members’ needs and opinions? The case study of the octopus fishery in the Algarve (south Portugal) M Rangel, C Pita, MM de Oliveira, MH Guimarães, R Rainha, ... Marine Policy 101, 276-284 , 2019 2019 Citations: 22
A system dynamics model to support the management of artisanal dredge fisheries in the south coast of Portugal JH Martins, AS Camanho, MM Oliveira, MB Gaspar International Transactions in Operational Research 22 (4), 611-634 , 2015 2015 Citations: 19
Evaluating the influence of skipper skills in the performance of Portuguese artisanal dredge vessels MM Oliveira, AS Camanho, JB Walden, MB Gaspar ICES Journal of Marine Science 73 (10), 2721-2728 , 2016 2016 Citations: 17
The influence of catch quotas on the productivity of the Portuguese bivalve dredge fleet MM Oliveira, AS Camanho, MB Gaspar ICES Journal of Marine Science 70 (7), 1378-1388 , 2013 2013 Citations: 16
The phycotoxins׳ impact on the revenue of the Portuguese artisanal dredge fleet MM Oliveira, AS Camanho, MB Gaspar Marine Policy 52, 45-51 , 2015 2015 Citations: 14
Enhancing the performance of quota managed fisheries using seasonality information: the case of the Portuguese artisanal dredge fleet MM Oliveira, AS Camanho, MB Gaspar Marine Policy 45, 114-120 , 2014 2014 Citations: 13
Portfolio efficiency analysis with SFA: the case of PSI-20 companies NB Ferreira, MM Oliveira Applied Economics 48 (1), 1-6 , 2016 2016 Citations: 12
Forecasting bivalve landings with multiple regression and data mining techniques: The case of the Portuguese Artisanal Dredge Fleet MM Oliveira, AS Camanho, JB Walden, VL Migueis, NB Ferreira, ... Marine Policy 84, 110-118 , 2017 2017 Citations: 10
Structural breaks and cointegration analysis in the EU developed markets N Ferreira, R Menezes, MM Oliveira International Journal of Latest Trends in Finance and Economics Sciences … , 2013 2013 Citations: 7
An analysis of equity markets cointegration in the European sovereign debt crisis NB Ferreira, MM Oliveira Open Journal of Finance, 40-48 , 2014 2014 Citations: 5
Artisanal fisheries analysis using the DPSIR framework and System Dynamics: the case of dredge fisheries in Portugal AS Camanho, J Hora, MM Oliveira, MB Gaspar FEUP/IPIMAR Report of the PRESPO Project, 30 , 2010 2010 Citations: 4
Review of fisheries studies applying DEA AS Camanho, J Hora, MM Oliveira, MB Gaspar 2011 Citations: 3
Analysis of the artisanal fisheries in the Atlantic Arc based on the DPSIR framework AS Camanho, J Hora, MB Gaspar, MM Oliveira FEUP/IPIMAR Report of Project PRESPO , 2010 2010 Citations: 3
Efficiency analysis of the Portuguese beam trawl fleet that targets the common prawn Palaemon serratus (Pennant) RJ Lopes, AS Rosa, LA Coelho, M Oliveira, MB Gaspar CEFAGE-UE working paper , 2008 2008 Citations: 3
Diclidophora luscae (Monogenea: Diclidophoridae) in pouting, Trisopterus luscus (Linnaeus, 1758) from the northeast Atlantic; epidemiology, morphology … P Ramos, R Varandas, IL Conceição, A Grade, MM Oliveira, ... Parasitology Research 121 (9), 2517-2535 , 2022 2022 Citations: 2
Assessing technical and economic efficiency of the artisanal dredge fleet in the Portuguese West Coast MM Oliveira, AS Camanho, MB Gaspar Operational Research: IO 2013-XVI Congress of APDIO, Bragança, Portugal … , 2015 2015 Citations: 2
Application of Bio-Economic Models in the Management of the Dredge Fleet in Portugal MMC de Oliveira PQDT-Global , 2014 2014 Citations: 1
